The study revealed that mandatory and preferred arrest laws were having the intended effect of producing higher domestic violence arrest rates in these States compared to States with discretionary arrest laws. These higher arrest rates were observed not only in intimate partner and other domestic violence cases, but in acquaintance and stranger cases as well. The study describes what is currently known about arrest practices; the research approach; research findings; and the policy implications and future research needs as a result of these findings. The primary focus was to examine the police response to intimate partner violence and the impact of mandatory and preferred arrest legislation on the police response. These findings suggest that laws have an effect on police operations, and that the domestic violence laws influence a broader range of cases than intended. The study’s data was limited to incidents in which the most serious offense reported to the police was aggravated assault, simple assault, or intimidation. In order to understand patterns and variations unique to domestic violence more fully, included were all cases of assault and intimidation, regardless of relationship. The police data for this study were taken from the 2000 National Incident Based Reporting System (NIBRS), which contains incident-based, victim-based, and offender-based information obtained by the police in every NIBRS jurisdiction. The NIBRS database was supplemented by variables taken from analysis of State statutes. A total of 577,862 incidents of assault and intimidation were reported to police in 2000. These cases involved 662,258 offenders and 650,849 victims. 6 tables, 73 notes
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